WattmonMEGA

WattmonMEGA is the most powerful of the Wattmon range of embedded data logging and control devices. This version has several I/O lines on-board, making it easy to develop intelligent machine automation applications in addition to performing data logging.

Wattmon is a versatile platform which can be configured for countless applications. The inbuilt web server provides all of the tools necessary to customize the device. No programming is required to set up actions based on various triggers, which can control I/O lines, send emails and more.

WattmonMEGA can run on a DC power source between 6 and 60V DC. It has a built in high efficiency switching buck regulator that ensures that it consumes less than 2 watts of power without accessory devices. The device can be shipped with an AC adapter or a DC power cable to be directly connected to your battery bank of up to 48V DC.

Connectivity

WattmonMEGA has two ways of connecting to the Internet. The built-in 100 Mbit LAN can be connected directly to a laptop or router, and is used for setup and local monitoring. The USB Host port works with a selected number of USB Cellular dongles, allowing both outbound and inbound data via the Internet. Although we provide instructions on configuring your local dongle, not all of them work. Need a compatible USB dongle for remote monitoring? Use one of our Huawei dongles, the E303F or E3531 for 2G/3G and or the E3372 for 4G.

Hardware Features

Serial (RS-232)

An RS-232 serial port allows you to interface with Inverters or other devices that can provide data. Drivers for Studer and Victron inverters are now provided along with the Wattmon, making it simple to remotely monitor your PV panels and energy information from the inverter itself.

Modbus RTU (RS-485)

An RS-485 Modbus RTU interface is built in and Wattmon acts as a Modbus master to collect data from various devices such as power meters, current sensors, etc.

If you are planning to monitor a battery bank with Wattmon, you will require a current sensor device such as the C252 (25A), C502 (50A) or C752 (75A).

Modbus TCP (Ethernet)

Up to 10 Modbus TCP channels to different IP addresses can be established. Multiple devices per IP address are possible. Read more: Modbus TCP in Wattmon.

Inputs and Outputs

The inputs and outputs and their various applications are described below.

4 digital inputs

Pings 16-19 are digital inputs. They are opto-isolated and can handle anywhere between 4 and 24V DC between the input pin and the DIGND pin. Pins 16-18 (DI1-DI3) can also be configured as pulse/frequency counters for measuring data from flow meters/anemometers, etc

4 digital outputs

These are open collector type (using a ULN2003 chip) and can be directly connected to 12V relays (with external power supply) to control high power loads - they can handle up to 500mA per pin.

Onboard relay

An on-board latching relay can switch DC or AC loads of up to 5 A. If higher loads are required, this relay can be used to power a larger one. The latching relay takes very little power to switch state and no power once toggled, so there is no difference in power draw whether the relay is on or off.

3 Analog inputs

WattmonPRO has three analog input channels, each with a 10-bit ADC on board (1024 possible values for the full scale).

Channel 1 also doubles as the voltage supply for the device. This is done so that when the device is running of a battery it's possible to measure the battery voltage directly from the supply. Max voltage is 60V DC.

Channel 2 is a voltage sense input that can be used to measure up to 330V DC for high voltage battery banks. The negative voltage terminal is shared with the main ground on pin 1.

WattmonPRO has a Dallas Onewire bus that allows for DS18B20 temperature sensors to be connected. This can be used for ambient temperature or battery temperature measurement. You can connectup to 8 sensors per device. See here for more information: Onewire Temperature Sensor